This invention relates to pneumatic outlets for covered hopper railcars and, more particularly, to an end adapter which fits onto the discharge end of the outlet.
Pneumatic outlets for covered hopper railway cars are well known in the art. See, for example, U.S. Pat. Nos. 4,114,785, 3,778,114, and 3,194,420, which are assigned to the same assignee as the present invention. Various types of granular or pelletized ladings are carried in hopper cars and are discharged from the car through these outlets. Such discharge involves connecting a hose to the outlet and creating an airstream in which the lading is entrained. With some ladings, plastic pellets, for example, the brushing or contact between the pellets and the outlet creates a charge of static electricity that is potentially dangerous. If the charge is not bled off by grounding the outlet, the charge may produce a spark which, in the right environment, could create a fire or cause an explosion. Because of this hazard, it would be advantageous to insulate the outlet so no charge is formed in the first place. Further, static electricity build-up may occur if a metal base is used, or if a metal reinforced hose is used and the metal is, for some reason, exposed. The conveying hose may loosely slip into a metal nozzle. Often, there is a gap between the hose and outlet which could result in a spark being produced.
In addition, if a short circuit condition exists in the offloading equipment, the short may find a path through the hose/valve connection, through the truck and truck wheels of the car, to ground. Such a condition is not only dangerous to persons using the equipment or working around the car, but may also damage the wheel bearings, for example, which may form part of the resultant circuit path through the car. Again, if the outlet were insulated, this condition may be prevented.